The EMC/EMI problem in the performance of electronic devices, such as printed circuit boards, refers to the lack of electromagnetic compatibility (EMC) of device components due to electromagnetic interference (EMI) between them. The EMC/EMI problem involves one device component (a source) generating an electromagnetic field that propagates through a coupling path to another device component (the receiver). The electromagnetic field induces the receiver to radiate an electromagnetic field that is different from what is desired of the receiver.
To test for and diagnose EMC/EMI problems, a designer or manufacturer of an electronic device may use a scanner to detect the electromagnetic field levels radiated by the electronic device. A spectral scan may be performed to determine electromagnetic field levels at a variety of desired frequencies. In addition or in the alternative, a spatial scan may be performed to map electromagnetic field levels at a designated frequency at different sampling locations relative to the electronic device. In this manner, a spatial scan can assist in identifying the components of the device that are responsible for an EMC/EMI problem.
In a spatial scan, it may be preferable for the distance between sampling locations of the spatial scan to be small relative to the size and spacing of the device components. For example, a resolution of less than a millimeter may be required to discriminate between the electromagnetic fields radiated by the miniaturized components packaged on a printed circuit board used in a compact cellular phone under test. However, decreased spacing between sampling locations increases the number of sampling locations for a given scan area and the time required to complete the spatial scan. For prior art scanners having a single probe, the probe must be moved to each and every sampling location, which can make it prohibitively time-consuming to perform a spatial scan having hundreds or thousands of sampling locations.
Accordingly, there is a need in the art for a scanner system that is operable to more efficiently perform high-resolution scanning of electronic devices.